JPH10222256A - Power controller and power control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the capacity of a battery from being eliminated within work schedule time and to prevent the ability of a processing circuit from being deteriorated for more than need. SOLUTION: In an information processor, a current detection device 24 and a one chip micro-computer 28 provided with the input function of a current detection device output signal and a function for controlling respective power consumption controllers are provided for power supply lines 22 supplying power from a battery 21 in addition to a former similar information processor. The one chip micro-computer 28 always monitors a current value consumed from the battery 21 and always suppresses power consumption to be not more than constant power by suitably controlling on/off of the power consumption device. Thus, battery driving time can securely realize work schedule time without deteriorating the ability of an information unit for more than necessity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power control device for adjusting the amount of power supplied by a battery according to the remaining capacity of the battery in an electronic device that operates by receiving power supplied from the battery. Hereinafter, a case where the power control apparatus is applied to an information processing apparatus will be described.

[0002]

2. Description of the Related Art FIG. 1 and FIG.
FIG. 1 shows an example of a conventional device of this type disclosed in Japanese Patent Application Laid-Open Publication No. 1 (1999). In FIG. 1, 1 is an information processing device, 2 is a CPU that controls the entire information processing device, 3 is a ROM that stores information that does not need to be rewritten such as a program, 4 is a RAM that stores information that needs to be rewritten such as variable data, 5 is CPU
Reference numeral 17 denotes a clock control unit which is a power consumption control function for controlling the operation clock of the second control unit.

[0003] 6 is a display panel such as a liquid crystal display,
Reference numeral 7 denotes a backlight device such as a cold-cathode tube for illuminating the display panel 6, reference numeral 8 denotes a backlight control unit which is a power consumption control function for controlling brightness / ON / OFF of the backlight device 7, and reference numeral 9 denotes a keyboard 10 and the like. I / O for controlling peripheral devices
The O control unit 10 is a keyboard on which a user performs input. The hardware configuration of this conventional example is as described above.
Next, a configuration for power consumption control of this example will be described. The power consumption control of this example is performed by using the hardware described above and a ROM
3. It is realized by software stored in the RAM 4 or the like and executed by the CPU 2.

As shown in FIG. 2, the control of the power consumption of this embodiment is functionally equivalent to a scheduled work input processing unit 11, a control method setting processing unit 12, a power consumption storage unit 13, a priority storage unit 14, and the like. It is composed of a scheduled work time learning processing unit 15 and a power consumption control unit 16. And by operating these parts independently or in cooperation,
Controlling power consumption.

Next, the operation will be described. When the user instructs the setting of the scheduled work time using the keyboard 10 or the like, the scheduled work time input processing unit 11 displays a predetermined input screen, and the user sets a desired work time T on the input screen. When confirming the completion of the setting of the scheduled work time, the scheduled work time input processing unit 11 transmits the set value to the control method setting processing unit 12. Then, the control method setting processing unit 12 controls the power consumption control method, for example,
The setting of darkness, the presence or absence of auto power off, the CPU clock frequency, and the like are changed according to the set value of the scheduled work time T.

In this conventional example, if the scheduled work time T is less than 2 hours, the backlight 7 is turned "bright" and the auto power off is not activated. Also, the clock frequency is set to 16 MHz. If the scheduled work time T is 2 hours or more and less than 5 hours, the backlight 7 is set to “dark” and the automatic power off is set to 10 minutes. The clock frequency is set to 8 MHz. When setting the specific conditions of the control method, the control method setting processing unit 12 exchanges information with the power consumption storage unit 13, the priority storage unit 14, and the scheduled work time learning processing unit 15.

After that, the power consumption control means 1
6, specifically, the backlight control unit 8, the power control unit 1
7. The clock control unit 5 adjusts each unit according to the control method. Thereby, the power consumption of the information processing device 1 is adjusted. That is, when the user sets the scheduled work time at the start of use of the information processing apparatus, the information processing apparatus automatically predicts and sets a power consumption control method for keeping the scheduled work time in advance.

[0008]

A conventional battery-operable information processing apparatus provided with scheduled work input means is configured as described above, and the control means and control level for power consumption control are unique before the start of work. When the same work is repeated with a fixed application, the battery drive time can substantially keep the scheduled work time.
When the user uses several types of applications arbitrarily as in C, the application non-use time in the entire work time and the I / O during application use
Since the access frequency and the CPU usage rate differ for each application, the battery drive time ends earlier than the scheduled work time, and the function of the information device is unnecessarily reduced by uniquely determining the clock frequency and the like.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is possible to prevent the battery from running out of capacity within a scheduled work time and to prevent the performance of the processing circuit from unnecessarily lowering. It is an object.

[0010]

A power control device according to the present invention includes a battery for supplying power to a processing circuit, a battery voltage measuring means for measuring a battery voltage of the battery, and a battery measured by the measuring means. A remaining capacity calculating means for calculating the remaining capacity of the battery from the voltage, a remaining power of the battery calculated by the remaining capacity calculating means, and a reference power amount to be supplied by the battery from a predetermined scheduled work time. A reference electric energy calculating means for calculating, an electric energy measuring means for measuring an actual electric energy supplied by the battery, and whether an actual electric energy measured by the electric energy measuring means exceeds the reference electric energy. Determining means for determining whether or not the processing circuit is operating, and adjusting means for adjusting an operation state of the processing circuit based on a determination result by the determining means A.

When the measured actual power is larger than the reference power, the adjusting means adjusts the power consumption of the processing circuit so as to reduce the power consumption. When the power consumption is smaller than the reference power amount, the power consumption of the processing circuit is adjusted so as to increase.

Further, the electric energy measuring means repeatedly measures an actual electric energy, and the adjusting means changes an operation state of the processing circuit based on the actual electric energy repeatedly measured by the electric energy measuring means. It is to adjust.

Still further, the processing circuit is a clock generating means for receiving a power supply from the battery and outputting a clock signal, and the adjusting means is configured to output the clock signal from the clock generating means based on a determination result by the determining means. The frequency of the generated clock signal is adjusted.

Further, the processing circuit is a display means for receiving power supply from the battery and displaying information, and the adjusting means, based on a judgment result by the judging means,
The display state of the display means is adjusted.

Further, the processing circuit is an LSI which operates by receiving power supply from the battery, and the adjusting means controls the LSI based on a result of the determination by the determining means.
This shuts off power supply to the SI.

Further, the processing circuit is an LSI which can be switched between at least two modes, a normal mode and a power save mode, and the adjusting means controls the mode of the LSI based on a determination result by the determining means. Is switched.

Further, there is provided input means for inputting the scheduled work time, wherein the reference electric energy calculating means is provided with the remaining capacity of the battery calculated by the remaining capacity calculating means and input by the input means. The reference power amount to be supplied by the battery is calculated from the estimated work time.

[0018] Further, there is provided storage means for storing the scheduled work time, wherein the reference electric energy calculating means includes a remaining capacity of the battery calculated by the remaining capacity calculating means and a work schedule stored by the storage means. The reference electric energy to be supplied by the battery is calculated from the time.

According to the power control method of the present invention, there is provided a battery voltage measuring step of measuring a battery voltage of a battery for supplying power, and a remaining capacity calculation of calculating a remaining capacity of the battery from the battery voltage measured in the battery voltage measuring step. And a power amount calculating step of calculating a reference power amount to be supplied by the battery from the remaining capacity of the battery calculated in the remaining capacity calculating step and a predetermined scheduled work time; and supplying from the battery. An electric energy measuring step of measuring an actual electric energy, a judging step of judging whether or not the actual electric energy measured by the electric energy measuring step exceeds a reference electric energy, based on a judgment result by the judging step Adjusting the operation state of a processing circuit that operates by receiving power supply from the battery Those having a settling step.

[0020] An input step of inputting the scheduled work time is provided.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In FIG. 3, reference numeral 20 denotes an extracted part of the information processing apparatus related to the present invention, reference numeral 21 denotes a battery serving as a power supply of the information processing apparatus 20, reference numeral 22 denotes a power supply line for supplying power from the battery 21 to an LSI or the like, reference numeral 34. Is a battery voltage line for transmitting a battery voltage, 23 is a power supply line 22
CPU that receives power supply via the clock line and operates based on a clock signal transmitted from the clock line 32,
23 is a set-up software operating within 23, 36 is a RAM for storing the scheduled work time set by the set-up software 35, and 24 is a power supply line 22.
And a current value output line 25 for transmitting a voltage output value of the current detection device after converting a current value flowing through the power supply line 22 into a voltage value and outputting the voltage value.

Reference numeral 26 denotes a two-input A / D converter for converting a voltage value input from the current value output line 25 and a voltage value input from the battery voltage line 34 into digital data, respectively. A digital output line for transmitting a digital output, 28 is a one-chip microcomputer having a digital value input function and a clock control output function, 29 is firmware operating in the one-chip microcomputer 28, and 30 is a clock control output of the one-chip microcomputer 28. This is a clock control line.

Reference numeral 31 denotes a clock control device for changing the frequency of a clock signal output by a control signal input from a clock control line 30, and 32 denotes a clock control device.
33, a clock line for transmitting a clock signal output from
Is a local bus to which the CPU 23 and the one-chip microcomputer 28 are connected. Reference numeral 10 denotes a keyboard for the operator to input a scheduled work time, which is a scheduled work time using the information processing device.

The operation of this embodiment will be described. As in the prior art, the user first gives a scheduled work time input instruction by the setup software 35 operating in the CPU 23, and inputs the planned work time using the keyboard 10. This scheduled work time is stored in the RAM 36. This scheduled work time is stored in the CPU 23 by the one-chip microcomputer 28.
Via the RAM 36 to obtain a current consumption upper limit value by a calculation formula described later, and use the clock controller 31 to control the CP value so that the current value of the power supply line 22 does not exceed this value.
The current consumption is controlled by changing the clock frequency of U23.

Hereinafter, a detailed description will be given. FIG. 4 is a flowchart showing the operation of the firmware 29 operating in the one-chip microcomputer 28. s8: The battery voltage is read from the two-input A / D converter 26. s9: The remaining battery capacity is calculated from the battery voltage by the following formula.

[0026]

(Equation 1)

The above formula assumes a battery having a linear discharge characteristic. If a non-linear battery is used, the one-chip microcomputer 28 has a built-in correspondence table showing the relationship between the battery voltage and the remaining battery capacity obtained by preliminary measurement, and determines the remaining battery capacity by referring to this table. . s1: The scheduled work time input by the user is read from the RAM. s2: By dividing the remaining battery value of the battery by the scheduled work time, an upper limit of the current consumption for use in battery driving during the scheduled work time is calculated, and this is referred to as a reference current value. The calculation formula for calculating the reference current value is as follows.

[0028]

(Equation 2)

S3: The current value of the current flowing through the power supply line 22 is read from the two-input A / D converter 26. s4: It is determined whether the current value of the current power supply line 22 exceeds the reference current value. If the power consumption is exceeded, the process proceeds to s5 to reduce the power consumption, and if not, the process proceeds to s6 to determine whether the power consumption may be increased. s5: A control signal for delaying the clock output by one stage is output to the clock control device 31, and the process returns to s3. The clock control device 31 receives a control signal from the one-chip microcomputer 28 and outputs a clock signal whose clock frequency is reduced by one stage. s6: It is determined whether or not the current actual current value is smaller than a value obtained by subtracting α (current value for providing hysteresis) from the reference current value. If it is small, the process proceeds to s7 to increase the power consumption. If it is large, the process returns to s3 so that the power consumption control is not changed.

The value α for providing hysteresis for preventing the clock frequency from being changed more than necessary must be appropriately adjusted by the information processing device. In the present embodiment, the value α decreases when the clock frequency is reduced by one step.電流 to of the current value to be set. s7: A control signal for increasing the clock output by one step to the clock control device 31 is output, and the process returns to s3. The clock control device 31 receives a control signal from the one-chip microcomputer 28 and outputs a clock signal whose clock frequency is increased by one step.

The power consumption is adjusted by performing the above processing. The above-described processing is performed not only immediately after the operator inputs the scheduled work time, but also is repeatedly performed at predetermined intervals, thereby enabling more accurate power consumption adjustment.

This is because if the above processing is performed only once immediately after the operator inputs the scheduled work time, if the same work is repeated with a fixed application,
Although the battery drive time can substantially keep the scheduled work time, when the user uses several types of applications arbitrarily as in a general PC, the application non-use time in the entire work time and the I / O during the application use are reduced. Since the O access frequency and the CPU usage rate differ for each application, the battery drive time ends earlier than the scheduled work time, and the information equipment function is unnecessarily reduced by uniquely determining the clock frequency and the like. is there.

On the other hand, if the above processing is repeatedly executed, the power consumption can be adjusted in accordance with the usage status of the application at that time, and the battery driving time ends earlier than the scheduled work time, and the clock frequency and the like are uniquely determined. By deciding, the problem of unnecessarily reducing the function of the information device is solved.

In this embodiment, since the current actual current value is compared with the reference current value to determine whether to reduce the power consumption, it is possible to prevent the battery from being exhausted within the scheduled work time. In addition, the performance of the information equipment is not unnecessarily reduced. In addition, since the clock frequency is particularly adjusted to reduce the power consumption, the power can be reduced while operating the CPU (or the entire system).

Further, since software for adjusting the clock frequency for reducing power consumption is built in the one-chip microcomputer 28, many companies cannot create basic system software such as BIOS which cannot be created by themselves. In addition, there is no need to incorporate software for adjusting a clock frequency into an O / S (operating system) to be purchased and installed in an information processing apparatus. Therefore,
These can be realized without customization.

In this embodiment, the actual current value flowing through the power supply line 22 is measured or the reference current amount is calculated. However, this measures the power amount supplied by the battery 21. And an example for calculating a reference power amount. Therefore, the process of measuring the actual current amount and calculating the reference current value is a process corresponding to the process of measuring the actual power amount and calculating the reference power amount.

Theoretically, it is also possible to recognize the amount of power supplied by the battery 21 by measuring the voltage value. However, in a secondary battery (nickel, nickel hydride, lithium ion) generally used as a battery, the discharge characteristics of the voltage value are not linear, so that the measurement accuracy is inferior.

In this embodiment, the expression (1)
Although equation (2) is used, the remaining battery capacity and the reference current amount may be calculated using other equations and the like. In this embodiment, the upper limit of the consumed current is set as the reference current amount, but it is not always necessary to set the upper limit. The reference current value is an index indicating an ideal value for using the battery power within the scheduled work time.

The clock control device 31 in this embodiment corresponds to a processing circuit that operates by receiving power supply from a battery. The firmware 29 includes a battery voltage measurement unit, a remaining capacity calculation unit, and a reference power amount. Calculating means;
It corresponds to an electric energy measuring unit, a determining unit, and an adjusting unit.

In this embodiment, a case has been described in which the user inputs the scheduled work time using the keyboard 10 each time the work is started. However, this is stored in a table or the like in which the scheduled work time is stored. Alternatively, the stored scheduled work time may be read. In any case, there is no change in calculating the reference power amount from the predetermined scheduled work time.

Embodiment 2 Hereinafter, the configuration of the second embodiment will be described with reference to the drawings. FIG. 5 shows the first embodiment shown in FIG.
The following points are changed from. (A) Delete the clock control line 30 (b) CPU clock down register 37, power management software 38, clock control register 39
Where 37 is the CPU 23 in the one-chip microcomputer 28
Are readable and writable, and “Up”, “Down”, “Lev
a CPU clock down register capable of setting three values of "el"; 38, power management software which operates in the CPU 23 and controls the clock control register 39 according to the instruction of the CPU clock down register 37;
Reference numeral 9 denotes a clock control register that controls the output frequency to the clock line 32 in the clock control device 31 and is readable and writable by the CPU 23. The clock control device 31 according to the second embodiment includes a case where the clock control device 31 is incorporated in an LSI in which CPU peripheral circuits called a core chipset are put together.

The operation of the second embodiment of the present invention will be described.
First, an outline will be described, and details will be described later using a flowchart. In the present embodiment, the clock control in the clock control device 31 performed in the first embodiment is not operated by the one-chip microcomputer 28, but is operated by the power management software 38 in the CPU 23 accessing the clock control register 39. I do. For this reason, the one-chip microcomputer 28 has a CPU clock down register 37 for notifying the power management software 38 of the clock change, and notifies the power management software 38 by changing this register. The CPU 23 is a CP in the one-chip microcomputer 28.
The notification is recognized by reading the U clock down register 37, and the clock frequency is controlled by operating the clock control register 39 in the clock control device 31. Less than,
The operation will be described in more detail.

A description will be given with reference to a flowchart of the firmware 29 operating in the one-chip microcomputer 28 and a flowchart of the power management software 38 operating in the CPU 23. Figure 6 shows one-chip microcomputer 2
8 is a flowchart showing the operation of the firmware 29 operating in the firmware 8. The operation is the same as that of the first embodiment except for the following points, and a description thereof will be omitted.

(A) As an alternative to s5 in FIG. 4 (a control signal for delaying the clock output by one step to the clock controller 31 and returning to s3), s10: CPU clock in the one-chip microcomputer 28 The “Down” value is set in the down register 37, and the process returns to s3.

(B) As a process instead of s7 in FIG. 4 (a control signal for increasing the clock output by one step to the clock controller 31 and returning to s3), s11: CPU clock in the one-chip microcomputer 28 The “Up” value is set in the down register 37, and the process returns to s3.

FIG. 7 is a flowchart of the power management software 38 operating in the CPU 23. Hereinafter, the operation will be described in order. s50: Read the value of the CPU clock down register 37 in the one-chip microcomputer 28. s51: The value of the CPU clock down register 37 is "D".
If "own", s52 is used to lower the clock frequency.
If not, proceed to s54. S52: A value is set in the clock control register 39 in the clock control device 31 so that the output clock is delayed by one step. The clock control device 31 checks the value set in the clock control register 39 and outputs a clock signal with a reduced clock frequency.

S53: The power management software 38 receives the notification from the one-chip microcomputer 28, and notifies the CPU clock down register 37 in the one-chip microcomputer 28 to notify the one-chip microcomputer 28 that the work of changing the clock frequency has been completed. “Level” is written, and the process returns to s50. s54: The value of the CPU clock down register 37 is "U"
If it is "p", the process proceeds to s55 in order to increase the clock frequency, and if it is not "Up", since it is "Level", the process returns to s50 without changing the clock frequency s55: Clock control in the clock control device 31 A value is set in the register 39 so that the output clock becomes one step faster, and the process proceeds to s3.The clock controller 31 checks the value set in the clock control register 39 and outputs a clock signal with a higher clock frequency. .

The effect of this embodiment will be described.
In this embodiment, since the current actual current value is compared with the reference current value to determine whether to reduce the power consumption, it is possible to prevent the battery from running out within the scheduled work time, The performance of the device will not be unnecessarily reduced. Further, since the clock frequency is adjusted by software by removing the clock control line 30, the present invention can be easily applied to an existing information processing apparatus. At present, in an information processing apparatus such as a personal computer, the clock control of the CPU is performed by software. Therefore, this embodiment in which the clock frequency is adjusted by software is easier to apply.

In this embodiment, the clock control device corresponds to a processing circuit, and the firmware 29
The battery voltage measurement unit, the remaining capacity calculation unit, the reference power amount calculation unit, the power amount measurement unit, and the determination unit correspond to each other, and the power management software 38 corresponds to the adjustment unit.

Embodiment 3 Hereinafter, the configuration of the third embodiment of the present invention will be described with reference to the drawings. FIG. 8 is obtained by adding the following changes from the first embodiment of the invention shown in FIG. (A) The clock control line 30, the clock control device 31, and the clock line 32 are deleted. (B) The function of the one-chip microcomputer 28 is changed. (C) Backlight control line 40, backlight control device 41, fluorescent tube AC output line 42, backlight device 4
3. Added display panel 44

Here, reference numeral 28 denotes a one-chip microcomputer having a function of outputting a control signal for controlling the brightness of the backlight, and 40 denotes a backlight control line for transmitting a control signal output from the one-chip microcomputer 28. Reference numeral 41 denotes a backlight control device such as an inverter for controlling the turning on / off of the fluorescent tube and the like in the backlight device 43 and brightness, and reference numeral 42 denotes a fluorescent tube AC output line for transmitting an output signal to the fluorescent tube of the backlight control device 41. Reference numeral 43 denotes a backlight device having a fluorescent tube or the like whose light-on / off and brightness change according to a signal input via the fluorescent tube AC output line 42, and 44 denotes a display such as an LCD for displaying a screen of the information processing device. It is a panel.

The operation of the third embodiment of the present invention will be described.
First, an outline will be described, and details will be described later using a flowchart. In the present embodiment, the one-chip microcomputer 28 controls the backlight control device 41 to change the luminance of the backlight and control the current consumption. Hereinafter, the operation will be described in detail.

The operation of the firmware 29 provided in the one-chip microcomputer 28 will be described with reference to a flowchart. FIG. 9 is a flowchart showing the operation of the firmware 29 provided in the one-chip microcomputer 28.
The operation is the same as that of the first embodiment except for the following points, and a description thereof will be omitted.

(A) As a process instead of s5 in FIG. 4 (a control signal for delaying the clock output by one step to the clock controller 31 and returning to s3), s12: the luminance is sent to the backlight controller 41. A control signal for darkening by one step is output, and the process returns to s3. The backlight control device 41 receives a control signal and controls the backlight device 43 so as to reduce the brightness of the backlight.

(B) As a process instead of s7 in FIG. 4 (a control signal for increasing the clock output by one step to the clock control device 31 and returning to s3), s13: the luminance is sent to the backlight control device 41. A control signal for increasing the brightness by one step is output, and the process returns to s3. The backlight control device 41 receives a control signal and controls the backlight device 43 so as to increase the brightness of the backlight.

Although the value α in s6 needs to be appropriately adjusted by the information processing device, in the present embodiment, the current value that decreases when the brightness of the backlight is reduced by one level is reduced to half to one third. 2 is set.

Hereinafter, the effect of this embodiment will be described. In this embodiment, since the current actual current value is compared with the reference current value to determine whether to reduce the power consumption, it is possible to prevent the battery from running out within the scheduled work time, The performance of the device will not be unnecessarily reduced. In this embodiment, the power consumption is adjusted by adjusting the brightness of the backlight. Therefore, since the backlight circuit is independent of the basic operation of the information processing device, the power can be efficiently reduced without affecting the system itself.

Further, since software for adjusting the brightness of the backlight for reducing the power consumption is built in the one-chip microcomputer 28, many companies are not allowed to create their own basic system such as BIOS.・
Software and O / S to be purchased and installed in information processing equipment
(Operating system) does not need to incorporate software for adjusting the brightness of the backlight.
Therefore, the present invention can be realized without customizing basic system software such as BIOS and O / S (operating system).

The backlight control device 41 according to this embodiment corresponds to a processing circuit that operates by receiving power supply from a battery. The firmware 29 includes a battery voltage measurement unit, a remaining capacity calculation unit, It corresponds to a reference power amount calculating unit, a power amount measuring unit, a determining unit, and an adjusting unit.

Embodiment 4 Hereinafter, the configuration of the fourth embodiment of the present invention will be described with reference to the drawings. FIG. 10 is a modification of the first embodiment of the invention shown in FIG. 3 with the following changes. (A) The clock control line 30, the clock control device 31, and the clock line 32 are deleted. (B) The function of the one-chip microcomputer 28 is changed. (C) power switch control line 45, function 46,
Power switch circuit 47, LSI power supply line 48, LS
I49, used / unused detection circuit 50, used / unused detection line 51 added.

Here, reference numeral 28 denotes a one-chip microcomputer having a function of outputting a power switch control signal and a function of inputting a used / unused detection signal, and 45 denotes a one-chip microcomputer 2
A power switch control line for transmitting a power switch control signal output from the LSI 8.
9 can be turned off and the LSI 4
This is a function that can detect use / non-use by the 9 detection devices outside.

47 is an LSI 49 in the function 46
A power switch circuit that supplies power to the LSI 49 in accordance with a power switch control signal of the one-chip microcomputer 45 and controls ON / OFF of power supply to the LSI 49. Reference numeral 48 denotes an LS that transmits the power supplied through the power switch circuit 47.
The I power supply line 49 is an LSI that realizes one function of the information processing device 20 and operates by receiving power supply via the power switch circuit 47.

Reference numeral 50 denotes a used / unused detecting circuit for detecting the used / unused state of the function 46 and outputting the detection result as a used / unused detecting signal. Reference numeral 51 denotes an output from the used / unused detecting circuit 50. Used / unused detection line for transmitting a used / unused detection signal.

The operation of the fourth embodiment will be described. First, an outline will be described, and details will be described later using a flowchart.
In the present embodiment, the one-chip microcomputer 28 detects use / non-use of the function 46 and
The power consumption is controlled by controlling a power supply switch circuit 47 for turning on / off the power supplied to the LSI 49 in 6. Hereinafter, the operation will be described in detail.

The operation of the firmware 29 provided in the one-chip microcomputer 28 will be described with reference to a flowchart. FIG. 11 is a flowchart showing the operation of the firmware 29 provided in the one-chip microcomputer 28. The operation is the same as that of the first embodiment except for the following points. However, since an s14 step is inserted, a description will be given again after describing the changed points.

(A) Insert s14 between s3 and s4. In s14, the following processing is performed. s14: The detection result is read from the used / unused detection circuit 50, and if it is in use, the function 46 cannot be saved in power, so the process returns to s3. If not, s4 is used for power control of the function 46. Proceed to. (B) As an alternative to s5 in FIG. 4 (output a control signal for delaying the clock output by one stage to the clock control device 31 and return to s3), s15: supply power to the LSI 49 to the power switch circuit 47. A power switch control signal which is a signal for turning off is output, and the process returns to s3. The power switch circuit 47 turns off power supply to the LSI 49 based on the power switch control signal.
F.

(C) s7 of FIG. 4 (clock controller 31)
And outputs a control signal for speeding up the clock output by one step.
Return to 3. S16: Output a power switch control signal, which is a signal for turning on the power supply to the LSI 49, to the power switch circuit 47, and return to s3. The power switch circuit 47 turns on the power supply to the LSI 49 based on the power switch control signal.
I do.

Although the value α in s6 needs to be appropriately adjusted by the information processing device, in this embodiment, the power supplied from the power switch circuit 47 to the LSI 49 is O
The value is set to one half to two half of the current value that decreases when the FF is performed.

Next, the entire operation of the firmware 29 will be described. s8: The battery voltage is read from the two-input A / D converter 26. s9: The remaining battery capacity is calculated from the battery voltage by the above equation (1). Equation (1) assumes a battery with a linear discharge characteristic. If a non-linear battery is used, a one-chip microcomputer has a built-in correspondence table showing the relationship between the battery voltage and the remaining battery capacity obtained by pre-measurement, and determines the remaining battery capacity by referring to this table. .

S1: The estimated work time input by the user is R
Read from AM36. s2: By dividing the remaining battery value of the battery by the scheduled work time, the upper limit of the current consumption for use in battery driving during the scheduled work time is calculated by the above equation (2). The calculated current consumption upper limit value is referred to as a reference current value.

S3: The current actual current value is input to two inputs A / D
Read from converter 26. s14: The detection result is read from the used / unused detection circuit 50, and if it is in use, the function 46 cannot be saved in power, so the process returns to s3. If not, s4 is used for power control of the function 46. Proceed to. s4: It is determined whether or not the current actual current value exceeds the reference current value, and if so, s is set to reduce power consumption.
The process proceeds to s6 if it is not exceeded, and to determine whether the power consumption may be increased. s15: A power switch control signal for turning off the power supply to the LSI 49 is output to the power switch circuit 47, and the process returns to s3.

S6: It is determined whether or not the current actual current value is smaller than a value obtained by subtracting α (current value for providing hysteresis) from the reference current value. If it is small, the process proceeds to s16 to increase the power consumption, and if it is large, the process returns to s3 so as not to change the power consumption control. It is necessary to provide a hysteresis to prevent the power supply to the LSI 49 from being turned ON / OFF more than necessary. The value α for providing the hysteresis needs to be appropriately adjusted by the information processing device. According to the present invention, the current value which decreases when the power supply to the LSI 49 is turned off is reduced to one half of the current value.
A value of two thirds is set. s16: A power switch control signal for turning on the power supply to the LSI 49 is output to the power switch circuit 47, and the process returns to s3.

The function 46 in this embodiment corresponds to, for example, an RS232C transmission / reception drive IC or a PC card power supply IC.
Determining whether or not the function 46 is being used in step 4 corresponds to, for example, determining whether or not a cable is inserted into the RS232C connector and whether or not a PC card is inserted into the PC card connector.

The effect of this embodiment will be described.
In this embodiment, since the current actual current value is compared with the reference current value to determine whether to reduce the power consumption, it is possible to prevent the battery from running out within the scheduled work time, The performance of the device will not be unnecessarily reduced. In this embodiment, the power supply of the LSI 49 is turned on / off to reduce power consumption.
Since the FF is performed, even a small amount of power consumption can be suppressed, and the power consumption can be reduced efficiently.

The LSI 49 in this embodiment is:
The firmware 29 corresponds to a processing circuit that operates by receiving power supply from a battery.
It corresponds to a remaining capacity calculation unit, a reference power amount calculation unit, a power amount measurement unit, a determination unit, and an adjustment unit.

Embodiment 5 Hereinafter, the configuration of the fifth embodiment of the present invention will be described with reference to the drawings. FIG. 12 is a modification of the first embodiment of the invention shown in FIG. 3 with the following changes. (A) The clock control line 30, the clock control device 31, and the clock line 32 are deleted. (B) The function of the one-chip microcomputer 28 is changed. (C) power management software 38, function 46, LSI 49, used / unused detection circuit 50,
Used / unused detection line 51, function ON / OFF
Added register 52.

Here, reference numeral 28 denotes a one-chip microcomputer having a function of inputting a used / unused detection signal, and 38 denotes a CPU.
Function ON / OFF register 5 which operates within 23
The power management software 46 controls the power save function of the LSI 49 in accordance with the instruction of 2. The CPU 23 controls the shift / return of the LSI 49 to the power save mode at the time of power save, and is used / not used by a detection device outside the LSI 49. It is a detectable function.

Reference numeral 49 denotes at least one of the information processing devices 20.
LSI that realizes one function, 50 is a function 46
Used / unused detection circuit 51 for detecting a used / unused state of the device and outputting a detection result as a used / unused detection signal
Is a used / unused detection line for transmitting a used / unused detection signal output from the used / unused detection circuit 50, and 52 is a function ON / OFF register provided in the one-chip microcomputer 28 and readable and writable by the CPU 23. It is. This function ON / OFF register 52
Can set two values of "ON" and "OFF".

The operation of the fifth embodiment of the present invention will be described.
First, an outline will be described, and details will be described later using a flowchart. In the present embodiment, the CPU 23 and the one-chip microcomputer 28 control the transition / return of the LSI 49 to the power save mode to control the current consumption.

The one-chip microcomputer 28 is in charge of detecting the use / non-use of the function 46. The control of the shift / return of the LSI 49 to the power save mode is performed by the CPU 23.
Power management software 38 in the system. For this reason, the one-chip microcomputer 28 has a function ON / OFF register 52 for notifying the power management software 38 of the transition to the power save mode or the return from the power save mode, and changes the set value of this register. Notify by The CPU 23
Function ON / OF in one-chip microcomputer 28
The notification is recognized by reading the set value of the F register 52, and the shift / return of the LSI 49 to the power save mode is controlled.

Hereinafter, the operation will be described in detail. The flowchart of the firmware 29 operating in the one-chip microcomputer 28 and the flowchart of the power management software 38 operating in the CPU 23 will be described. FIG. 13 is a flowchart showing the operation of the firmware 29 provided in the one-chip microcomputer 28.
The operation is the same as that of the first embodiment except for the following points.
Since 14 steps are inserted, the changed point is described, and then the description is repeated.

(A) Insert s14 between s3 and s4. In s14, the following processing is performed. s14: The detection result is read from the used / unused detection circuit 50, and if it is in use, the function 46 cannot be saved in power, so the process returns to s3. If not, s4 is used for power control of the function 46. Proceed to. (B) As an alternative to s5 in FIG. 4 (output a control signal for delaying the clock output by one step to the clock controller 31 and return to s3), s17: Function O in the one-chip microcomputer 28
"OFF" value is set in the N / OFF register 52, and s3
Return to

(C) s7 of FIG. 4 (clock controller 31)
And outputs a control signal for speeding up the clock output by one step.
Return to 3. S18: Function O in the one-chip microcomputer 28
The "ON" value is set in the N / OFF register 52, and the process returns to s3. Note that the value α in s6 needs to be appropriately adjusted by the information processing device.
9 is set to a value that is one half to one half of the current value that decreases when the mode is shifted to the power save mode.

Next, the entire flowchart will be described. s8: The battery voltage is read from the two-input A / D converter 26. s9: The remaining battery charge is calculated from the battery voltage by the above equation (1). Expression (1) assumes a battery having a linear discharge characteristic. If you use a non-linear battery,
The one-chip microcomputer 28 has a built-in correspondence table showing the relationship between the battery voltage and the remaining battery capacity obtained by the preliminary measurement, and determines the remaining battery capacity by referring to this table. s1: The scheduled work time input by the user is read from the RAM. s2: By dividing the remaining battery capacity value by the scheduled work time, the upper limit of the current consumption for use in battery driving during the scheduled work time is calculated. This consumed current upper limit is called a reference current value.

S3: The current value is read from the two-input A / D converter 26. s14: The detection result is read from the used / unused detection circuit 50, and if it is in use, the function 46 cannot be saved in power. Returning to s3, if not in use, proceed to s4 for power control of the function 46. s4: It is determined whether or not the current actual current value exceeds the reference current value, and if so, s is set to reduce power consumption.
The process proceeds to step S17, and if not, the process proceeds to step s6 to determine whether the power consumption may be increased.

S17: An "OFF" value is set in the function ON / OFF register 52 in the one-chip microcomputer 28, and the process returns to s3. s6: It is determined whether or not the current actual current value is smaller than a value obtained by subtracting α (current value for providing hysteresis) from the reference current value. If it is small, the process proceeds to s18 to increase the power consumption. If it is large, the process returns to s3 so that the power consumption control is not changed.

The value α for providing hysteresis for preventing the transition / return of the LSI 49 to the power save mode from occurring more than necessary must be appropriately adjusted by the information processing apparatus. The current value is reduced by one half to one half when the mode is changed to the save mode.
Is set. s18: Function O in the one-chip microcomputer 28
The "ON" value is set in the N / OFF register 52, and the process returns to s3.

FIG. 14 is a flowchart of the power management software 38 operating in the CPU 23. s56: Function ON in one-chip microcomputer 28
The setting value of the / OFF register 52 is read. s57: If the value of the function ON / OFF register 52 is "OFF", proceed to s52 to shift to the power save mode, otherwise proceed to s59.

S58: The LSI 49 is shifted to the power save mode, and returns to s56. s59: The LSI 49 is returned from the power save mode to the normal mode, and returns to s56.

Generally, the LSI 49 has a software register for shifting to the power save mode and returning to the normal mode. By setting this software register, the LSI 49 shifts to the power save mode and returns to the normal mode. It becomes possible. As the LSI 49, for example, an RS232C interface LSI or the like is applicable. In the case of the LSI for the RS232C interface, the operation is not performed in the power save mode, and the mode is shifted to the normal mode only when a telephone call signal “Ring-In” is received, and the reception operation is performed.

The effect of this embodiment will be described.
In this embodiment, since the current actual current value is compared with the reference current value to determine whether to reduce the power consumption, it is possible to prevent the battery from running out within the scheduled work time, The performance of the device will not be unnecessarily reduced. Also, it is checked whether or not the function 46 is being used, and if the function 46 is not used, the LSI 49 is shifted to the power save mode.
By shifting the information processing apparatus 9 to the power save mode, it is possible to prevent the information processing apparatus from functioning properly.

The LSI 49 in this embodiment is:
The firmware 29 corresponds to a processing circuit that operates by receiving power supply from a battery.
The power management software 38 corresponds to a remaining capacity calculation unit, a reference power amount calculation unit, a power amount measurement unit, and a determination unit.

Embodiment 6 FIG. Hereinafter, the configuration of the sixth embodiment of the present invention will be described with reference to the drawings. FIG. 15 is a modification of the first embodiment of the invention shown in FIG. 3 with the following changes. (A) The clock control line 30, the clock control device 31, and the clock line 32 are deleted. (B) The function of the one-chip microcomputer 28 is changed. (C) The power management software 38, the function 46, the LSI 49, and the function ON / OFF.
Register 52 added

Here, reference numeral 28 denotes a one-chip microcomputer having a firmware 29 and a function ON / OFF register.
This is power management software that controls the power saving function of the LSI 49 according to an instruction from the N / OFF register 52. 46 is an LSI49 at power save
Is a function that allows the CPU 23 to control the shift / return to the power save mode, and the CPU 23 can detect the use / non-use of the LSI 49; 49, an LSI realizing at least one function of the information processing apparatus 20; A function ON / OFF register provided in the microcomputer 28 and readable by the CPU 23. This function ON / OFF register 52
Can set two values of "ON" and "OFF".

The operation of the sixth embodiment of the present invention will be described.
First, an outline will be described, and details will be described later using a flowchart. In the present embodiment, the CPU 23 and the one-chip microcomputer 28 control the transition / return of the LSI 49 to the power save mode to control the current consumption.

The one-chip microcomputer 28 issues a function ON / OFF instruction. The power management software 38 in the CPU 23 detects the use / non-use of the function 46 and shifts / returns the LSI 49 to the power save mode. Therefore, one-chip microcomputer 2
8 has a function ON / OFF register 52 for notifying the power management software 38 of the transition to the power save mode or the return from the power save mode, and the function ON / OFF register 52 is notified by changing this register. The CPU 23 recognizes the notification by reading the function ON / OFF register 52 in the one-chip microcomputer 28, determines use / non-use of the LSI 49, and shifts the LSI 49 to the power save mode if not used.
Operate return.

The details will be described below. The flowchart of the firmware 29 operating in the one-chip microcomputer 28 and the flowchart of the power management software 38 operating in the CPU 23 will be described. FIG.
6 is a flowchart showing the operation of the firmware 29 provided in the one-chip microcomputer 28. The operation is the same as that of the first embodiment except for the following points.

(A) s5 in FIG. 4 (clock controller 31)
To output a control signal that delays the clock output by one step,
Return to 3. S17: Function O in the one-chip microcomputer 28
The "OFF" value is set in the N / OFF register 52, and the process returns to s3. (B) As an alternative to s7 in FIG. 4 (a control signal for increasing the clock output by one step to the clock controller 31 and returning to s3), s18: Function O in the one-chip microcomputer 28
The "ON" value is set in the N / OFF register 52, and the process returns to s3.

The value α in s6 needs to be appropriately adjusted by the information processing device.
The current value which is reduced when the I49 is shifted to the power save mode is set to a value which is 1/2 to 2/3.

FIG. 17 is a flowchart of the power management software 38 operating in the CPU 23. s56: Function ON in one-chip microcomputer 28
S60: Read the use / non-use information from the LSI 49,
If it is in use, the operation in the power save mode is not performed, so the process returns to s56. If it is not in use, the process proceeds to s57 to perform the operation in the power save mode.

S57: If the value of the function ON / OFF register is "OFF", the flow proceeds to s58 to shift to the power save mode; otherwise, the flow proceeds to s59 to return from the power save mode. S58: The LSI 49 Shift to power save mode,
Return to s56. s59: The LSI 49 is returned from the power save mode to the normal mode, and returns to s56.

As described above, in the sixth embodiment, the use / non-use detection circuit 50 and the use / non-use detection line 51 shown in the fifth embodiment are deleted, and C
The power management software 38 in the PU detects the use state of the function by software.

The effect of this embodiment will be described.
In this embodiment, since the current actual current value is compared with the reference current value to determine whether to reduce the power consumption, it is possible to prevent the battery from running out within the scheduled work time, The performance of the device will not be unnecessarily reduced.

The LSI 46 in this embodiment corresponds to a processing circuit that operates by receiving power supply from a battery, and the firmware 29 includes a battery voltage measurement unit, a remaining capacity calculation unit, a reference power amount calculation unit, The power management software 38 corresponds to an adjusting unit, and corresponds to the power amount measuring unit and the determining unit. Further, in the above embodiment, in order to adjust power consumption, adjustment of clock frequency, brightness adjustment of backlight, ON / OFF of LSI, etc.
And the like are performed independently, the power consumption may be adjusted by appropriately combining them. Furthermore, when a plurality of adjustments are performed in combination, it is possible to more appropriately adjust the power consumption by setting in advance which adjustments are to be prioritized. For example, by lowering the priority of clock control and giving priority to other controls, power consumption can be adjusted as much as possible without reducing the processing speed of the information processing apparatus.

[0105]

Since the present invention is configured as described above, it has the following effects. The power control device according to the present invention includes: a battery that supplies power to a processing circuit; a battery voltage measurement unit that measures a battery voltage of the battery; and a remaining capacity of the battery calculated from the battery voltage measured by the measurement unit. Remaining power calculation means, and the remaining power of the battery calculated by the remaining capacity calculation means, and a reference power amount calculation means for calculating a reference power amount to be supplied by the battery from a predetermined scheduled work time, Power amount measurement means for measuring the actual amount of power supplied by the battery, and determination means for determining whether the actual amount of power measured by the power amount measurement means exceeds the reference power amount, Adjusting means for adjusting the operation state of the processing circuit based on the result of the determination by the determining means. It is possible to prevent that the amount is eliminated, it is possible to prevent the dropping unnecessarily the performance of the processing circuit.

When the measured actual power is larger than the reference power, the adjusting means adjusts the power consumption of the processing circuit so as to reduce the power consumption. When the power consumption is smaller than the reference power amount, the power consumption of the processing circuit is adjusted so as to increase, so that the performance of the processing circuit can be prevented from being unnecessarily reduced.

Further, the power amount measuring means repeatedly measures the actual power amount, and the adjusting means changes the operation state of the processing circuit based on the actual power amount repeatedly measured by the power amount measuring means. Since the adjustment is performed, flexible power control according to the operation situation becomes possible, and the control accuracy is improved.

Further, the processing circuit is clock generating means for receiving a power supply from the battery and outputting a clock signal, and the adjusting means is configured to output the clock signal from the clock generating means based on the result of the judgment by the judging means. Since the frequency of the generated clock signal is adjusted, the power can be reduced while operating the entire device.

Further, the processing circuit is a display unit for displaying information by receiving power supply from the battery, and the adjusting unit is configured to execute the processing based on the determination result by the determining unit.
Since the display state of the display unit is adjusted, the display unit can efficiently reduce power without affecting the basic operation of the device itself.

Further, the processing circuit is an LSI that operates by receiving power supply from the battery, and the adjusting means determines the L level based on the determination result by the determining means.
Since power supply to the SI is cut off, power consumption can be reduced efficiently.

Further, the processing circuit is an LSI switchable between at least two modes of a normal mode and a power save mode, and the adjusting means determines a mode of the LSI based on a determination result by the determining means. , Power consumption can be reduced efficiently while at least necessary functions of the LSI are left.

Further, there is provided input means for inputting the scheduled work time, wherein the reference electric energy calculating means is provided with the remaining capacity of the battery calculated by the remaining capacity calculating means and the input by the input means. Since the reference electric energy to be supplied by the battery is calculated from the estimated work time, the estimated work time corresponding to the time can be input.

Further, there is provided storage means for storing the scheduled work time, wherein the reference power amount calculating means includes the remaining capacity of the battery calculated by the remaining capacity calculation means and the work schedule stored by the storage means. Since the reference electric energy to be supplied by the battery is calculated from the time, it is not necessary to input the scheduled work time each time.

A power control method according to the present invention includes a battery voltage measuring step of measuring a battery voltage of a battery supplying power, and a remaining capacity calculating step of calculating a remaining capacity of the battery from the battery voltage measured in the battery voltage measuring step. And a power amount calculating step of calculating a reference power amount to be supplied by the battery from the remaining capacity of the battery calculated in the remaining capacity calculating step and a predetermined scheduled work time; and supplying from the battery. An electric energy measuring step of measuring an actual electric energy, a judging step of judging whether or not the actual electric energy measured by the electric energy measuring step exceeds a reference electric energy, based on a judgment result by the judging step Adjusting the operation state of a processing circuit that operates by receiving power supply from the battery Because having a settling step, it is possible to prevent that the capacity of the battery is eliminated, it is possible to prevent the dropping unnecessarily the performance of the processing circuit.

Since the method further comprises an input step of inputting the scheduled work time, the scheduled work time corresponding to each time can be input.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a conventional information processing apparatus.

FIG. 2 is a functional block diagram of power control of a conventional information processing apparatus.

FIG. 3 is a configuration diagram of an information processing apparatus according to the first embodiment.

FIG. 4 shows a one-chip microcomputer 2 according to the first embodiment.
8 is a flowchart of the firmware 29 in FIG.

FIG. 5 is a configuration diagram of an information processing apparatus according to a second embodiment.

FIG. 6 shows a one-chip microcomputer 2 according to the second embodiment.
8 is a flowchart of the firmware 29 in FIG.

FIG. 7 is a flowchart of power management software 38 in a CPU 23 according to the second embodiment.

FIG. 8 is a configuration diagram of an information processing apparatus according to a third embodiment.

FIG. 9 shows a one-chip microcomputer 2 according to a third embodiment.
8 is a flowchart of the firmware 29 in FIG.

FIG. 10 is a configuration diagram of an information processing device according to a fourth embodiment.

FIG. 11 is a flowchart of firmware 29 in one-chip microcomputer 28 according to the fourth embodiment.

FIG. 12 is a configuration diagram of an information processing device according to a fifth embodiment.

FIG. 13 is a flowchart of firmware 29 in one-chip microcomputer 28 according to the fifth embodiment.

FIG. 14 is a flowchart of the power management software 38 in the CPU 23 according to the fifth embodiment.

FIG. 15 is a configuration diagram of an information processing device according to a sixth embodiment.

FIG. 16 is a flowchart of firmware 38 in one-chip microcomputer 28 according to the sixth embodiment.

FIG. 17 is a flowchart of the power management software 29 in the CPU 23 according to the sixth embodiment.

[Explanation of symbols]

1 information processing device, 2 CPU, 3 ROM, 4R
AM, 5 clock control unit, 6 LCD panel, 7 backlight device, 8 backlight control unit, 9 I / O control unit, 10 keyboard, 11 scheduled work input processing unit, 12 control method setting processing unit, 13 power consumption storage Means, 14 priority storage means, 15 scheduled work time learning processing section, 16 power consumption control means, 17 power supply control section, 20
Information processing device, 21 battery, 22 power supply line, 2
3 CPU, 24 current detection device, 25 current value output line,
26 2-input A / D converter, 27 digital output line, 28 one-chip microcomputer, 29 firmware, 30 clock control line, 31 clock control device, 3
2 clock line, 33 local bus, 34 battery voltage line, 35 setup software, 36 R
AM, 37 CPU clock down register, 38
Power management software, 39 clock control register, 40 backlight control line, 41 backlight control device, 42 AC output for fluorescent tube, 43 backlight device, 44 LCD panel, 45 power switch control line, 46 function, 47 power switch circuit, Power supply line for 48 LSI, 49 LSI, 5
0 Used / unused detection circuit, 51 used / unused detection line, 52 function ON / OFF register.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroaki Ishikawa 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (11)

[Claims] A battery for supplying power to a processing circuit; a battery voltage measuring means for measuring a battery voltage of the battery; and a remaining capacity for calculating a remaining capacity of the battery from the battery voltage measured by the measuring means. Calculation means; reference power amount calculation means for calculating a reference power amount to be supplied by the battery from the remaining capacity of the battery calculated by the remaining capacity calculation means and a predetermined scheduled work time; Power amount measuring means for measuring the actual power amount being supplied; determining means for determining whether the actual power amount measured by the power amount measuring means exceeds the reference power amount; And an adjusting unit that adjusts an operation state of the processing circuit based on a result of the determination. 2. The method according to claim 1, wherein the adjusting unit adjusts the power consumption of the processing circuit so as to reduce power consumption when the measured actual power amount is larger than the reference power amount. 2. The power control device according to claim 1, wherein when the power consumption is smaller than a reference power amount, the power consumption of the processing circuit is adjusted to increase. 3. The power amount measuring means repeatedly measures an actual power amount, and the adjusting means changes an operation state of the processing circuit based on the actual power amount repeatedly measured by the power amount measuring means. The power control device according to claim 1, wherein the power control device performs adjustment. 4. The processing circuit is clock generation means for receiving a power supply from the battery and outputting a clock signal. The adjustment means is generated by the clock generation means based on a determination result by the determination means. 4. The power control device according to claim 1, wherein the frequency of the clock signal is adjusted. 5. The processing circuit is a display unit that receives power supply from the battery and displays information, and the adjustment unit adjusts a display state of the display unit based on a determination result by the determination unit. The power control device according to any one of claims 1 to 3, wherein: 6. The processing circuit is an LSI that operates by receiving power supply from the battery, and the adjusting unit cuts off power supply to the LSI based on a result of the determination by the determining unit. The power control device according to any one of claims 1 to 3, wherein 7. The processing circuit is an LSI switchable between at least two modes of a normal mode and a power save mode, and the adjusting unit switches the mode of the LSI based on a result of the determination by the determining unit. The power control device according to any one of claims 1 to 3, wherein: 8. An input means for inputting the scheduled work time, wherein the reference power amount calculating means receives the remaining capacity of the battery calculated by the remaining capacity calculating means, and receives the input by the input means. The power control device according to claim 1, wherein a reference power amount to be supplied by the battery is calculated from the estimated work time. 9. A storage unit for storing the scheduled work time, wherein the reference power calculating unit calculates the remaining capacity of the battery calculated by the remaining capacity calculating unit and the scheduled work stored by the storage unit. 7. The power control device according to claim 1, wherein a reference power amount to be supplied by the battery is calculated from the time. 10. A battery voltage measuring step of measuring a battery voltage of a battery supplying electric power, a remaining capacity calculating step of calculating a remaining capacity of the battery from the battery voltage measured in the battery voltage measuring step, A power amount calculating step of calculating a reference power amount to be supplied by the battery from the remaining capacity of the battery calculated by the calculation step and a predetermined scheduled work time; and measuring an actual power amount supplied from the battery. A power measurement step, a determination step of determining whether an actual power measured by the power measurement exceeds a reference power, and a power from the battery based on a determination result of the determination. Adjusting the operation state of the processing circuit that operates by receiving the supply. Power control method according to claim. 11. The power control method according to claim 10, further comprising an input step of inputting the scheduled work time.